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arXiv · 1609.07225

Boson Stars in Higher Derivative Gravity

Abstract

In this paper, we have constructed Boson star (BS) solutions in four dimensional scalar-Gauss-Bonnet (sGB) theory. In order to have non-trivial effect from Gauss-Bonnet term, we invoked non-minimal coupling between a complex scalar field and the Gauss-Bonnet term with a coupling parameter, $\alpha$. We show that the scalar field can no longer take arbitrary value at the center of the star. Furthermore, boson-stars in our higher derivative theory turn out to be slightly massive but much more compact than those in the usual Einstein's gravity. Interestingly, we found that for $\alpha<-0.4$ and $\alpha>0.8$, binding energy for all possible boson stars is always negative. This implies that these stars are intrinsically stable against the decay by dispersion. We also present the mass-radius and mass-frequency curves for boson-star and compare them with other compact objects in gravity models derived from Gauss-Bonnet term.

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BibTeXRIS

Vishal Baibhav, Debaprasad Maity. 2016-09-23. Boson Stars in Higher Derivative Gravity. https://doi.org/10.1103/physrevd.95.024027

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